Portable derricks



R. O. BALOGH PORTABLE DERRICKS May 15, 1962 2 Sheets-Sheet l Filed Jan. 14, 1955 May 15, 1962 R. o. BALOGH '3,034,658

PORTABLE DERRICKS Filed Jan. 14, 1955 2 Sheets-Sheet 2 FIG. 8.

INVENToR.

ROY O. BALoGl-l 3 BY *ElA l,

3,034,653 PURTABLIE DECKS Roy G. Balogh, Clayton, Mo., assigner to McCabe- Powers Body Company, a corporation of Missouri Filed Jan. 14, 1955, Ser. No. 481,779 3 Claims. (Qi. 212-8) nited States Patent O Workmen may ride, and tool and supply compartments in which equipment used in service and maintenance operations may be stored. Because much of the equipment used by telephone companiesand electric companies is mounted in elevated position upon poles, the service and maintenance trucks are ordinarily provided with some type of derrick which can be used in lifting equipment up and down, setting poles, removing worn out or defective poles and replacing them, and similar types of work. In this connection, one of the problems frequently encountered has to do with the lifting of heavy equipment from the truck body to the ground and then elevating it to the pole. This is quite common in the repair or replacement of transformers. The transformer, being a very heavy piece of equipment, is difficult to move from the truck to a position from which it cany be elevated to the pole and, similarly, the transformer which is being replaced must be lowered from the pole on which it is mounted and placed in the truck body, but usually the poles and transformers are located to the side of the road and the truck `body cannot be in a truly level position during these work-operations so that considerable ditliculty is experienced in handling heavy equipment of this type with conventional types of portable derricks. Similarly, when it is necessary to remove a worn or damaged pole and replace it with a new one, the work must be performed in a location which is comparatively inconvenient and to which there is no level access so that the conventional types of derricks can only be used with great difliculty. Finally, conventional types of portable derricks usually must be dismantled ywhen the job is completed so that the legs and other components can be stored within the truck and must be assembled and set up again when the truck reaches the next worklocation. If a crew is setting a series of poles along a street or roadway, this becomes a very burdensome type of operation because the derrick must be lowered, dismantled, reassembled and erected at frequent intervals.

It is, therefore, the primary object of the present invention to provide a vehicle-mounted or portable derrick which is completely power operated and can be swung from inoperative transport position to upright or workposition by power driven means quickly, eiciently and with a minimum of manual labor` It is also an object of the present invention to provide a vehicle-mounted derrick of the type stated which, when in operative position, can be swung forwardly and rearwardly and from side to side by power driven means and is 'thus capable of reaching any desired position irrespective of the position or inclination of the truck bodies on which it is mounted.

It is a further object of the present invention to provide a portable derrick of the type stated which can be manipulated to and from transport position and into various operative positions by a single operator and is ICC capable of a wider range of movement than conventional types of portable derricks.

It is an additional object of the present invention to provide a portable derrick of the type stated which is uniquely adapted for lifting heavy loads from the ground upwardly and into the cargo area 0f the `body outwardly and downwardly as the circumstances of the work may require.

With the above and other objects in view, my invention resides in the novel features of form, construction, arrangement, and combination of parts presently described and pointed out in the claims.

In the accompanying drawings (two sheets)- FIGURE l is a side elevational View of a utility maintenance truck equipped with a portable derrick constructed in accordance with and embodying the present invention;

FIGURE 2 is a diagrammatic view of the hydraulic system forming a part of the present invention;

FIGURE 3 is a fragmentary rear elevational view of the utility maintenance truck equipped with a portable derrick constructed in accordance with and embodying the present invention;

FIGURE 4 is a fragmentary side elevational view showing the derrick in upright or work-position;

FIGURE 5 is a fragmentary sectional View taken along line 5 5 of FIGURE l;

FIGURE 6 is a fragmentary sectional View taken along line 6 6 of FIGURE 5; and

' FIGURES 7 and 8 are fragmentary sectional views taken along lines 7 7 and 8 8, respectively, of FIG- URE 1.

Referring now in more detail and by reference characters to the drawings, which illustrate a preferred embodiment of the present invention, A designates a utility maintenance truck equipped with a so-called utility body 1 having the usual crew compartment 2 in the forward end just rearward of the drivers cab c and rearwardly extending side walls 3, t, disposed in spaced parallel relation along the opposite longitudinal margins of the body. The side walls 3, 4, are provided with a series of built-in cabinets 5, 6, 7, 8, for the storage of tools, small parts, and similar items of equipment ordinarily used by repair crews. The side walls 3, 4, are spaced outwardly from each other and, together with the rear wall 9 of the cab compartment, deline a cargo area a which is open at the top and rear. Mounted on the lloor 10 adjacent to the crew compartment 2 is a conventional cable winch assembly 11 having a cable 12.

The floor 10 is extended rearwardly beyond the rear vertical faces of the side walls 3, d, in the provision of 1an extension 13 provided on its under face with depending clevis-brackets 14 from which ground jacks 15 are suspended. Welded upon the upper face of the extension 13 and along the rear face of the side walls 3, 4, are two vertical upright posts 16, each provided with a pair of spaced ,vertical flanges 17, 18, arranged to form a` vertical slideway for shiftably receiving Ia slide block 19 extending therethrough and held in place by means of a cap plate 2li and retainer screws 21. The slide blocks 19 project outwardly from the posts 16 and are integrally provided with upwardly opening U-shaped clevis elements 22 adapted for receiving the flattened ends 23 of derrick legs Zd, the latter being pivotally held in'place by pivot pins 25, all as best seen in FIGURES 5 and 6.

Threadedly mounted at their vupper ends in the lower portions of the clevis elements 22 are piston rods 26,

operatively disposed at their lower ends within hydraulic cylinders 27, the latter being of conventional construction and, therefore, not described herein in specific detail.

The derrick legs 24 converge inwardly toward each other and at their outer ends are rockably connected to each other by a swivel fitting 28 having a head sheave 29 and guide rollers 30. Welded to each derrick leg 24 downwardly from the sheave block 28- are triangular brackets 31 pivotally connected by means of a pivot pin 32 to the upper end litting 33 of piston rods 34, which are, in turn, operatively mounted in hydraulic pistons 35, the latter, at their lower ends, being pivotally connected by means of pivot pins 36 to upstanding swivel brackets 37 which are, in turn, welded or otherwise rigidly mounted upon the top faces of the side walls 3, 4, respectively. The hydraulic cylinders 27, 27, 35, 35, are connected through conventional hand-operated shutoff valves p and a main control valve V to a hydraulic system substantially as shown in FIGURE 2. The valve V may be of any conventional internal construction and includes control handles h1, [12, h3, h4, so that each one of the four `cylinders 27, 27, 35, 35, can be individually controlled.

The portable derrick is ordinarily lowered to inoperative or horizontal position as shown in FIGURE l and rests at its forward end in a somewhat L-shaped transport rack R rigidly carried on the forward wall of the truck body 1 and extending upwardly and forwardly over the drivers cab c. In order to raise the derrick to the operative position shown in FIGURE 4, oil is admitted to the cylinders 35, pushing the piston rods 34 outwardly and accordingly swinging the derrick upwardly and rearwardly. The vertical height of the head sheave 29 can be varied by admitting oil to the upper ends of the cylinders 27, 27, forcing the piston rods 26 thereof downwardly, lowering the derrick to the position shown in dotted lines in FIGURE 4. It will, of course, be understood that oil must also be admitted to the cylinders 35 to permit further extension of the piston rods 34 in lowering the derrick to this horizontal position. It will also be understood that by manipulating the various valve handles h1, h2, h3, h4, dierent amounts of oil can be admitted to the various cylinders 27, 27, 35, 35, so that the derrick can be caused to assume virtually any position of forward, rearward, or sideward angulation within the maximum limits of travel permitted by the various component elements thereof. For example, the cylinders 35, 35, can be adjusted so that the head sheave 29 is located more or less vertically above the cargo area a in order that the cable 12 can be dropped vertically into the cargo area a for attachment to a heavy object, such as the transformer switch box or the like, whereupon the heavy article can be lifted vertically up from the floor of the truck and suspended. Thereupon, by admitting further oil into the cylinders 35, 35, the head sheave 29 can be swung rearwardly over and beyond the rear end of the truck body 1, thereby transporting the suspended heavy article rearwardly beyond the truck body into the clear from which latter position it can be lowered to the ground or raised up to pole-height. When a heavy object such as a transformer is being lifted by the cable 12, the derrick A may be locked in the particular position to which it has been adjusted by closing the hand shut-off valves p.

Similarly, in pole-setting operations it is possible, by appropriate manipulation of the four cylinders 27, 27, 35, 35, to cause the head sheave 29 to move in a true vertical line without change in its angulation with respect to the truck body 1, thus a pole can be lifted vertically up out of the hole or lowered vertically downwardly into a hole in the ground as may be desired, thus materially facilitating and speeding up the handling of `this type of service or maintenance operation.

It should be understood that changes and modifications in the form, construction, arrangement, and combination of the several parts of the portable derrick may be made and substituted for those herein shown and described without departing from the nature and principle of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A portable derrick comprising a mobile platform having vertical uprights provided with opposed parallel slideways, slide elements shiftably mounted in said slideways, a pair of derrick legs rockably connected together at one end and extending divergently outwardly from each other in the form of an inverted V, a sheave-block carried by the derrick legs at such rockably connected end, said derrick legs being pivotally connected at their lower ends to the respective slide elements, separate power driven means individually connected to each of the slide elements for shifting said slide elements within the slideways, separate power driven means connected individually to each of the derrick legs outwardly from the pivoted ends thereof, and separately operable manual control means associated with each of said power driven means for permitting independent movement of each of the power driven means so as to swing the sheave-block through an arc which lies in the medial plane between the paths of movement of the slide elements and also into various positions laterally with respect to said medial plane within the maximum limits of travel permitted by the pivotal connections.

2. A portable derrick comprising a mobile platform having vertical uprights provided with opposed parallel slideways, slide elements shiftably mounted in said slideways, a pair of derrick legs rockably connected together at one end and extending divergently outwardly from each other in the form of an inverted V, a sheave-block carried by the derrick legs at such rockably connected end, said derrick legs being pivotally connected at their lower ends to the respective slide elements, separate power driven means individually connected to each of the slide elements for shifting said slide elements within the slideways, separate power driven means connected individually to each of the derrick legs outwardly from the pivoted ends thereof, and separately operable manual control means associated with each of said power drive means for permitting independent movement of each of the power driven means so as to swing the sheave-block through an arc which lies in a plane located approximately midway between, and parallel to, said slideways and also into varous positions laterally with respect to said plane within the maximum limits of travel permitted by the pivotal connections.

3. A portable derrick comprising a mobile platform having vertical uprights provided with opposed parallel slideways, slide elements operatively mounted in said slideways, a pair of derrick legs connected together at one end and extending divergently outwardly from each other in the form of an inverted V, a sheave-block carried by the derrick legs at said connected end, said derrick legs being pivotally connected at their lower ends to the respective slide elements, hydraulic cylinders operatively connected to the slide elements for shifting said slide elements within the slideways, hydraulic means connected to the derrick legs outwardly from the pivoted ends thereof for swinging the derrick legs pivotally with respect t0 the slide elements, and means for supplying oil to each of the hydraulic cylinders, said means including valves adapted for optionally permitting independent and conjoint operation of said hydraulic cylinders so as to shift said seave through an arc lying in a plane parallel to said slideways and also to and fro laterally of said plane `within the limits of travel permitted by said pivotal connections.

References Cited in the file of this patent UNITED STATES PATENTS 2,557,466 Richards et al June 19, 1951 2,611,580 Troche et al Sept. 23, 1952 2,687,811 Hurst Aug. 31, 1954 

